Professor of Polymer Engineering, Dipartimento di Chimica Industriale e Ingegneria Chimica, Politecnico di Milano, Milano,
Professor and Head of the Mechanical Engineering Department, Imperial College of Science, Technology and Medicine, London,
Pages: 16 Published: Jan 2000
This paper describes research work undertaken by the Technical Committee on Polymers and Composites (TC4) of the European Structural Integrity Society (ESIS) to develop a standardized testing procedure for conducting KIC and GIC tests on plastics at a moderately high rate of loading, namely a load-point displacement rate of 1 m/s. One of the authors (A. P.) has acted as the task group leader for this activity within the Committee, with responsibility for the preparation of the testing protocol, the coordination of interlaboratory round-robins and the analysis of data generated thereby. The proposed testing procedure stems from the linear elastic fracture mechanics scheme covered in a protocol for “quasi-static” (low loading rate) determination of KIC and GIC which was developed within the same ESIS group previously.
In this paper the background for the extension of the scope of the preceding protocol to higher rates is illustrated, the problems encountered are highlighted and the solutions found and proposed in the final draft of the protocol are reviewed. A summary of the test results obtained in a series of round-robin exercises — which involved some thirty laboratories across Europe on a five-year span — is reported and the significance of interlaboratory consistency of the collected data is commented upon with the view of validating the protocol. In conclusion, it is pointed out that an agreed standardized procedure can be finalized to form the basis of national and international standards.
polymer fracture, toughness, fracture energy, impact testing, fracture testing standards
Paper ID: STP14347S